1. Technical Field
The present disclosure relates to a printed circuit board with a patterned electrically conductive layer therein visible and a method for manufacturing the same.
2. Description of Related Art
A printed circuit board with a patterned electrically conductive layer visible includes a light-pervious insulation layer, a patterned electrically conductive layer formed on the light-pervious insulation layer, and a light-pervious overlay covering the patterned electrically conductive layer. A material of the patterned electrically conductive layer is copper. Opposite surfaces of the patterned electrically conductive layer are blackened through a black oxide treatment. The black color of the patterned electrically conductive layer seen through the light-pervious insulation layer and overlay causes the printed circuit board to have a remarkable appearance. A method of related art for manufacturing the printed circuit board may include steps as follows: firstly, a copper clad laminate is provided. The copper clad laminate comprises the light-pervious insulation layer and a copper foil with opposite surfaces oxidized to be black. Secondly, the copper foil is partly etched to form the patterned electrically conductive layer. Finally, the overlay is laminated over the patterned electrically conductive layer to form the printed circuit board.
However, inner surfaces of the patterned electrically conductive layer are defined interconnecting the two opposite surfaces after the etching process. The inner surfaces of the patterned electrically conductive layer present a red brown color because parts of the copper foil have been etched to expose the inner copper layer of the copper foil. This may cause an aesthetically-unacceptable appearance of the patterned electrically conductive layer.
What is needed therefore is a printed circuit board with a patterned electrically conductive layer visible and a method for manufacturing the same to overcome the described limitations.